Triangle read by rows: T(n,k) is the number of simple graphs on n unlabeled nodes having chromatic number k, 1 <= k <= n.

A084268

Triangle read by rows: T(n,k) is the number of simple graphs on n unlabeled nodes having chromatic number k, 1 <= k <= n.

Terms

    a(0) =1a(1) =1a(2) =1a(3) =1a(4) =2a(5) =1a(6) =1a(7) =6a(8) =3a(9) =1a(10) =1a(11) =12a(12) =16a(13) =4a(14) =1a(15) =1a(16) =34a(17) =84a(18) =31a(19) =5a(20) =1a(21) =1a(22) =87a(23) =579a(24) =318a(25) =52a(26) =6a(27) =1a(28) =1a(29) =302

External references